Not sure if already added but thought of sharing as is really good and 100% FREE antivirus and anti-malware from Microsoft.

This has been there for quite some time and i have been using this for long and is really good and reliable.

Use Microsoft Security Essentials to guard against viruses, spyware, and other evil software. It provides real-time protection for your home or small business PCs.

Microsoft Security Essentials is free* and we designed it to be simple to install and easy to use. It runs quietly and efficiently in the background so you don't have to worry about interruptions or making updates.

MSE just doesnt cut it neither do any of the other free av's i tested this by installing 1 at a time leaving it a month while downloading torrents and selecting random sites of the un-official wiki on the deep web, then ran a full scan with a free av once that had finished plugged in my pen drive with titanium av on and ran another scan. Every month i tested this it found things that the free av's looked over, so if you use the web for more than just surfing be safe buy an av!

Forgot malwarebytes trial was good and it was unlimited but last time i went to install it on pc the trail only lasted a month, you could always d/l a keygen and get the full thing for free (a keygen usualy triggers any av with a false positive) but to be safe run it in sand boxie

Ive used AVG, norton, mcafee and other antiviruses, but to be honest this is the best 1 and I have been using this for well over a year and its light on the memory and does a great job. Never had any issues with installing it like others have here. Works a charm and ill stick with it, im sick of other av's that are so heavy on memory and you need to keep renewing the serial numbers or deal with pop ad screens. This is just impressive for a MS release.